Add oats, collagen peptides, and baking powder to a high speed blender and blend on high for 30-60 seconds or until you have a fine oat flour mixture.
Add the wet ingredients to the blender (banana, eggs, milk) and blend on high for 30-60 seconds or until smooth.
Pour the oat mixture into either one 8x8 baking dish or two individual oven-safe dishes (see notes).
Add chocolate chips and walnuts to the oat mixture and stir to combine.
Bake in the preheated oven for 18 to 22 minutes. When it's done, a toothpick will come out with just a few crumbs on it, but not wet.
Enjoy immediately or store in an airtight container in the refrigerator for 3-4 days. To serve, simply reheat for 30-60 seconds in the microwave.
Notes
These are my favorite unflavored collagen peptides. They don't change the texture or taste of the baked oats recipe.Enjoy it as is or you could top it with your favorite toppings like a scoop of plain greek yogurt, cottage cheese, fresh fruit, or a drizzle of your favorite nut butter like almond butter or cashew butter.See full blog post above for more variations, substitutions, and tips.